Delivery system and method for the effective and reliable delivery of controlled amounts of a medical fluid

ABSTRACT

A method for performing a medical procedure requiring effective, reliable and foolproof delivery of controlled amounts of a medical grade gas to a patient includes providing a compressed gas cylinder having a weight with medical grade gas sealed therein of at least twelve grams and not greater than fifty grams. The method also includes connecting the compressed gas cylinder to an integrated compressed gas unit including a regulator valve assembly positioned between an outlet port and an inlet port, wherein the regulator valve assembly includes a press button actuator and regulator adjustment dial. A flow control system is secured to the compressed gas unit and the medical grade gas is delivered in precisely controlled amounts by actuating the compressed gas unit and operating the flow control system to deliver the medical grade gas to vasculature of the patient.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of Ser. No. 14/497,657,entitled “Delivery System For The Effective, Reliable And FoolproofDelivery Of Controlled Amounts Of A Medical Fluid,” filed Sep. 26, 2014,which is currently pending, which is continuation in part of U.S. patentapplication Ser. No. 13/857,448, filed Apr. 5, 2013, entitled “PortableMedical Gas Delivery System”, which is currently pending, which is acontinuation in part of U.S. patent application Ser. No. 13/068,680,filed May 17, 2011, entitled “Apparatus and Process for Producing CO2Enriched Medical Foam”, which is now U.S. Pat. No. 8,876,749, which is acontinuation in part of U.S. patent application Ser. No. 12/652,845,filed Jan. 6, 2010, entitled “Portable Medical Gas Delivery System”,which is abandoned, which is a continuation in part of U.S. patentapplication Ser. No. 12/210,368, filed Sep. 15, 2008, entitled “PortableMedical Foam Apparatus”, which is abandoned, which is a continuation inpart of U.S. patent application Ser. No. 11/945,674, filed Nov. 27,2007, entitled “Portable Evaporative Snow Apparatus”, now U.S. Pat. No.7,543,760, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/867,323, filed Nov. 27, 2006, entitled “PortableEvaporative Snow Apparatus”, and U.S. patent application Ser. No.14/497,657, entitled “Delivery System For The Effective, Reliable AndFoolproof Delivery Of Controlled Amounts Of A Medical Fluid,” filed Sep.26, 2014, which is currently pending, is a continuation in part of U.S.patent application Ser. No. 13/065,621, filed Mar. 25, 2011, entitled“System for Controlled Delivery of Medical Fluids”, which is now U.S.Pat. No. 9,050,401, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/395,892, filed May 19, 2010, entitled “Systemfor Controlled Delivery of Medical Fluids”;

and this application is a continuation in part of Ser. No. 14/497,691,entitled “Delivery System For The Effective, Reliable And FoolproofDelivery Of Controlled Amounts Of A Medical Fluid,” filed Sep. 26, 2014,which is currently pending, which is continuation in part of U.S. patentapplication Ser. No. 13/857,448, filed Apr. 5, 2013, entitled “PortableMedical Gas Delivery System”, which is currently pending, which is acontinuation in part of U.S. patent application Ser. No. 13/068,680,filed May 17, 2011, entitled “Apparatus and Process for Producing CO2Enriched Medical Foam”, which is now U.S. Pat. No. 8,876,749, which is acontinuation in part of U.S. patent application Ser. No. 12/652,845,filed Jan. 6, 2010, entitled “Portable Medical Gas Delivery System”,which is abandoned, which is a continuation in part of U.S. patentapplication Ser. No. 12/210,368, filed Sep. 15, 2008, entitled “PortableMedical Foam Apparatus”, which is abandoned, which is a continuation inpart of U.S. patent application Ser. No. 11/945,674, filed Nov. 27,2007, entitled “Portable Evaporative Snow Apparatus”, now U.S. Pat. No.7,543,760, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/867,323, filed Nov. 27, 2006, entitled “PortableEvaporative Snow Apparatus”, and U.S. patent application Ser. No.14/497,691, entitled “Delivery System For The Effective, Reliable AndFoolproof Delivery Of Controlled Amounts Of A Medical Fluid,” filed Sep.26, 2014, which is currently pending, is a continuation in part of U.S.patent application Ser. No. 13/065,621, filed Mar. 25, 2011, entitled“System for Controlled Delivery of Medical Fluids”, which is now U.S.Pat. No. 9,050,401, which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/395,892, filed May 19, 2010, entitled “Systemfor Controlled Delivery of Medical Fluids”;

and this application is a continuation in part of U.S. patentapplication Ser. No. 13/569,444, filed Aug. 8, 2012, entitled“Disposable Cartridge For Holding Compressed Gas”, which is currentlypending, which is a continuation in part of U.S. patent application Ser.No. 13/068,680, filed May 17, 2011, entitled “Apparatus and Process forProducing CO2 Enriched Medical Foam”, which is now U.S. Pat. No.8,876,749, which is a continuation in part of U.S. patent applicationSer. No. 12/652,845, filed Jan. 6, 2010, entitled “Portable Medical GasDelivery System”, which is abandoned, which is a continuation in part ofU.S. patent application Ser. No. 12/210,368, filed Sep. 15, 2008,entitled “Portable Medical Foam Apparatus”, which is abandoned, which isa continuation in part of U.S. patent application Ser. No. 11/945,674,filed Nov. 27, 2007, entitled “Portable Evaporative Snow Apparatus”, nowU.S. Pat. No. 7,543,760, which claims the benefit of U.S. ProvisionalPatent Application Ser. No. 60/867,323, filed Nov. 27, 2006, entitled“Portable Evaporative Snow Apparatus”, the disclosures of which areincorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a portable system for safely and efficientlyproducing and delivering CO₂ and other gases for use in medicalapplications.

2. Description of the Related Art

Conventional devices for delivering gas such as carbon dioxide (CO₂) foruse in medical procedures typically utilize large storage tanks andregulators. Such devices are dangerous because of the risk of a seal,valve or part malfunction, which can produce a projectile in a medicalsetting. In addition, existing tank systems are quite expensive,extremely cumbersome and usually impractical to transport to off-sitelocations. These systems typically require a considerable amount ofstorage space. Current tanks also require filling at a filling station,which can involve the transport of a large quantity of gas such as CO₂.Pressurized gas tanks can explode in the event of a motor vehicle crash.Re-fellable tanks can also exhibit rust, bacteria and contamination,which are not acceptable in a medical environment.

Still further, various types of medical equipment have been utilized todeliver controlled volumes of liquid and gaseous substances to patients.One field that involves the administration of such fluids is radiology,wherein a small amount of carbon dioxide gas or an alternative contrastmedia may be delivered to the vascular system of the patient to displacethe patient's blood and obtain improved images of the vascular system.Traditionally, this has required that the CO₂ or other media first bedelivered from a pressurized cylinder to a syringe. The filled syringeis then disconnected from the cylinder and reconnected to a catheterattached to the patient. If additional CO₂ is needed, the syringe mustbe disconnected from the catheter and reattached to the cylinder forrefilling Not only is this procedure tedious and time consuming, itpresents a serious risk of introducing air into the CO₂ or contrastfluid at each point of disconnection. Injecting such air into thepatient's blood vessels can be extremely dangerous and even fatal.

Recinella et al., U.S. Pat. No. 6,315,762 discloses a closed deliverysystem wherein a bag containing up to 2,000 ml of carbon dioxide orother contrast media is selectively interconnected by a stopcock toeither the chamber of a syringe or a catheter attached to the patient.Although this system does reduce the introduction of air into theadministered fluid caused by disconnecting and reconnecting theindividual components, it still exhibits a number of shortcomings. Forone thing, potentially dangerous volumes of air are apt to be trappedwithin the bag. This usually requires the bag to be manipulated andflushed multiple times before it is attached to the stopcock andultimately to the catheter. Moreover, this delivery system does notfeature an optimally safe and reliable, foolproof operation. If thestopcock valve is incorrectly operated to inadvertently connect thecarbon dioxide filled bag or other source of carbon dioxide directly tothe patient catheter, a dangerous and potentially lethal volume of CO₂may be delivered suddenly to the patient's vascular system. It ismedically critical to avoid such CO₂ flooding of the blood vessels.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a systemfor safely and reliably delivering a controlled dosage of a fluid to amedical patient.

It is a further object of this invention to provide a fluid (i.e. liquidor gas) delivery system that is particularly effective for use inadministering CO₂ or other contrast media in a controlled manner to apatient's vascular system to provide improved contrast for radiologicalimaging.

It is a further object of this invention to provide a fluid deliverysystem and particularly a CO₂/contrast media delivery system thatprevents potentially dangerous amounts of air from entering the fluidand thereby being administered to the patient.

It is a further object of this invention to provide a fluid deliverysystem that prevents accidentally flooding of the patient's vascularsystem with carbon dioxide or other administered gases or liquids underpositive pressure.

It is a further object of this invention to provide a fluid deliverysystem exhibiting a failsafe and foolproof operation, which permits onlyreliable and accurately controlled dosages of a medical fluid to beadministered to a patient.

It is a further object of this invention to provide a fluid deliverysystem that may be used safely and effectively with virtually any sourceof carbon dioxide or other medical fluid regardless of the pressure orenvironment under which that fluid is maintained.

It is a further object of this invention to provide a fluid flow systemthat prevents an administered medical fluid from flowing in anunintended direction through the system.

In accordance with these objects, the present invention provides amethod for using carbon dioxide as a contrast material in medicalimaging procedures. The method includes providing a source ofpressurized carbon dioxide, connecting the source of pressurized carbondioxide to a compressed gas unit including a solenoid for controllingdelivery of the carbon dioxide, regulating pressure of the carbondioxide delivered by the compressed gas unit and transmitting thepressurized carbon dioxide from the compressed gas unit to a controlvalve assembly for delivery to a patient in controlled dosages.Thereafter, the carbon dioxide is sequentially processed with thecontrol valve assembly and delivered to the patient as a contrast media.

It is also an object of the present invention to provide a methodwherein the step of sequentially processing includes delivering carbondioxide through a series of syringes such that it is impossible todirectly connect the compressed gas unit to the patient.

It is also an object of the present invention to provide a methodwherein the step of sequentially processing includes providing inlet andoutlet conduits connected respectively to the compressed gas unit andthe patient. The method also includes providing first and secondsyringes and the control valve assembly, which are interconnectedbetween the inlet and outlet conduits.

It is also an object of the present invention to provide a methodwherein the control valve assembly includes a valve body having alignedinlet and outlet ports that are respectively communicably connectable tothe inlet conduit and the outlet conduits. The valve body furtherincludes a first intermediate port to which the first syringe isselectively connected and a second intermediate port to which the secondsyringe is selectively connected. The control valve assembly furtherincludes a stopcock element mounted rotatably within the body andincluding a channel consisting essentially of a first channel segmentand a second channel segment. The first channel segment and the secondchannel segment are selectively alignable with the inlet port and thefirst intermediate port to allow for communication between the inletconduit and the first syringe. The first intermediate port and thesecond intermediate port allow for communication between the firstsyringe and the second syringe, and the second intermediate port and theoutlet port to allow for communication between the second syringe andthe outlet conduit.

It is also an object of the present invention to provide a methodwherein the step of sequentially processing includes operating thecontrol valve assembly to communicably join the compressed gas unit andthe first syringe and transmitting carbon dioxide from the compressedgas unit to only the first syringe, adjusting the control valve assemblyto communicably join the first and second syringes while isolating thefirst syringe from the compressed gas unit, operating the first syringeto transmit carbon dioxide from the first syringe to only the secondsyringe through the control valve assembly, adjusting the control valveassembly to communicably join the second syringe to the outlet conduitand to isolate the first syringe and the compressed gas unit from thesecond syringe, and operating the second syringe to transmit carbondioxide from the second syringe to only the patient through the outletconduit.

Other objects and advantages of the present invention will becomeapparent from the following detailed description when viewed inconjunction with the accompanying drawings, which set forth certainembodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of a delivery system in accordance with thepresent invention.

FIG. 2 is a perspective view of the compressed gas unit with a capsulesecured thereto.

FIG. 3 is a front plan view of the compressed gas unit shown in FIG. 2.

FIG. 4 is a side plan view of the compressed gas unit shown in FIG. 2.

FIG. 5 is a schematic of a compressed gas unit in accordance with analternate embodiment.

FIG. 6 is a schematic front view of an alternative compressed gas unitenclosed in a housing.

FIG. 7 depicts a schematic layout of the components of the compressedgas unit of FIG. 2.

FIG. 8 is a view similar to FIG. 1 wherein the control valve assembly isenlarged for clarity and the internal construction of the valve assemblyis illustrated.

FIGS. 9A, 9B and 9C showing the internal operating components of thestopcock in its various operating modes.

FIG. 10 is a simplified, schematic view of the outlet conduit and analternative downstream fitting that may be used to interconnect theoutlet conduit to the patient catheter.

FIG. 11 is a view similar to that of FIGS. 4-6 which depicts amedication administering syringe being attached to the downstreamfitting by means of a connecting tube.

FIG. 12 is a perspective view of a control valve assembly featuring adual handle for operating the stopcock and indicating which pair of flowpassageways is open.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The detailed embodiments of the present invention are disclosed herein.It should be understood, however, that the disclosed embodiments aremerely exemplary of the invention, which may be embodied in variousforms. Therefore, the details disclosed herein are not to be interpretedas limiting, but merely as a basis for teaching one skilled in the arthow to make and/or use the invention.

Referring to the various figures, and in particular FIG. 1, the presentinvention provides a delivery system 10 for the effective, reliable andfoolproof delivery of controlled amounts of a medical fluid such as CO₂or other contrast media to a patient. In accordance with the presentinvention, delivery is achieved through the utilization of an integratedcompressed gas unit 12 and a multi-part valve delivery system 14. Themulti-part valve delivery system 14 delivers the fluid in preciselycontrolled amounts sequentially through a series of syringes such thatit is impossible to directly connect the fluid source to the patient. Atthe same time, the delivery system 10 does not have to be disconnectedand reconnected during the administration of medical fluid. This greatlyreduces the intrusion of air into the system and the fluid beingadministered.

With reference to FIGS. 2-4, the integrated compressed gas unit 12 isdisclosed. The integrated compressed gas unit 12 includes an inlet port16 to which at least one compressed gas (CO₂) cylinder 18 is selectivelyconnected and an outlet port 20 in communication with the inlet port 16,and ultimately the at least one compressed gas (CO₂) cylinder 18.

The compressed gas cylinder 18 is secured to, and maintained in fluidcommunication with, the integrated compressed gas unit 12 by a cylindercartridge puncture valve 22 and a fitting 24 formed at the inlet port 16of the integrated compressed gas unit 12. In accordance with a preferredembodiment, the cylinder cartridge puncture valve 22 has a mechanism forpiercing the compressed gas cylinder 18, as is known in the art, and forholding or securing the compressed gas cylinder 18 in place.

The compressed gas exits the inlet port 16 and passes through aregulator valve assembly 26 controlled by a press button actuator 28 andregulator adjustment dial 30. The regulator valve assembly 26 dictatesthe pressure of the gas as it ultimately exits the outlet port 20. Inaccordance with a preferred embodiment, the regulator valve assembly 26has a selective outlet pressure in the range of 7 psi to 19 psi. Theoutlet pressure is achieved by rotating the regulator adjustment dial 30of the button actuator 28. In addition, to regulating the appliedpressure, the regulator valve assembly 26 also includes a valve 26 vthat controls the passage of gas from the inlet port 16 to the outletport 20. The valve 26 v is controlled via a push button mechanism 28 pin the button actuator 28 such that a user may selectively determinewhen gas may pass therethrough to the outlet port 20. In accordance witha preferred embodiment, the CO₂ flow rate is less than 12 NL/min.

As mentioned above, the regulator valve assembly 26 also includes aregulator adjustment dial 30 which controls the pressure permitted toexit the outlet port 20 by either rotating the regulator adjustment dial30 clockwise or counterclockwise as may be desired to adjust the appliedpressure. The applied pressure may be monitored using the PSI gaugeformed on the front face 32 of the integrated compressed gas unit 12.

In practice, a compressed gas cylinder 18 is applied to the integratedcompressed gas unit 12 in the following manner. The adjustment dial 30is first disengaged (loosened) by rotating the same in acounter-clockwise direction. The compressed gas cylinder 18 is thenscrewed into the fitting 24 and the cylinder cartridge puncture valve 22punctures compressed gas cylinder 18. The system is then actuated as byengaging the adjustment dial in a clockwise direction and operating thesame as described above through the manipulation of the press buttonactuator 28 and the adjustment dial 30.

As mentioned above, the outlet port 20 is in fluid communication withthe inlet port 16 for transport of gas in accordance with the presentinvention. The outlet port 20 is provided with a luer connection 34 forthe secure and selective attachment of an outlet tube 36 thereto.

Referring now to FIG. 5, an alternate embodiment of a compressed gasunit 112 in accordance with the present invention is disclosed. Thecompressed gas unit includes a solenoid 155 with at least one compressedgas (CO) cylinder 118 connected communicably to the solenoid 155. Thecompressed gas cylinder 118 is secured into position to the compressedgas unit 112 by means of cylinder cartridge puncture valve 126 and afitting 174. In a preferred embodiment, the cylinder cartridge puncturevalve 126 has a mechanism for piercing the cylinder 118, as is known inthe art, and for holding or securing the cylinder 118 in place.Compressed air is delivered to the solenoid 155 from the compressed gascylinder 118 through the cylinder cartridge puncture valve 126 and theconduit 173 of the fitting 174. The conduit 173 of the fitting 174communicates with a threaded conduit 138 described more fully below.

The compressed gas unit 112 has at least one battery 165 held in placeby a battery holder 142, for providing electrical power by which thesolenoid 155 may be selectively activated and opened by a pressureactivation switch or activation switch 137. The activation switch 137 isdesigned so that the solenoid 155 is opened when a physician or othermedical personnel engages the activation switch 137 by voluntarilyapplying a small predetermined amount of fingertip pressure to theactivation switch 137. It is not activated by a breathing sensor orother actuators designed to be operated by involuntary movement of theuser's body. The battery 165 supplies power to the solenoid 155 througha switch wire assembly 123, which is connected to the activation switch137. The activation switch 137 is mounted to a pressure nut 132 carriedon threaded conduit 138. The compressed gas unit 112 has electricalwiring 139 for providing necessary electricity from the activationswitch 137 to the solenoid 155.

The compressed gas unit 112 also comprises a separate black rockregulator 143, which is distinct from the solenoid 155. The black rockregulator 143 is controlled or adjusted by a regulator adjustment knob130 to provide a selected level of pressure to the gas provided to thesolenoid 155. The black rock regulator 140 is communicably connected tothe compressed gas unit 112 by an elbow pipe 140. The elbow pipe 140includes a threaded vertical conduit segment 141 joined to the blackrock regulator 143 through a connector nut and the threaded horizontalconduit 138, which is engaged by pressure nut 132.

As discussed above, the compressed gas cylinder 118 is secured to thecompressed gas unit 112 by the cartridge puncture valve 126 as iscommonly known. In one embodiment, the compressed gas cylinder 118 is a25 gram cylinder. Alternative capacities (e.g. 16, 36, 45 grams) may beused within the scope of this invention. Compressed air leaves the blackrock regulator 143 at the regulator adjusted pressure through a 10/32″hose port 113 b and flows through a hose junction 122, by means of a ⅛″pressure hose 154, until reaching the 10/32″ hose port 113 a affixed tothe solenoid 155. From the hose port 113 a, the compressed air entersthe solenoid 155. The compressed air unit 112 also has an outlet airport 125, which is connected to the solenoid 155 through intermediate10/32″ hose port 113 a for transporting compressed gas, namely CO2 fromthe solenoid 155 in the compressed gas unit 112 to the flow controlsystem when the solenoid 155 is opened. Outlet gas may be monitored witha pressure gauge 152 connected to the hose junction 122 through aconduit 145 having threads 146. The threaded end of the conduit 145interengages a nut 148 carried by the hose junction 122.

In certain embodiments a second compressed gas cylinder or cartridge128, featuring a 16 g or 25 g compressed gas cylinder, may be used inaddition to or in lieu of the primary gas cylinder 118. In still otherembodiments, a larger compressed gas cylinder and expansion chamber maybe substituted for the gas cartridges previously described in accordancewith the invention. The size and number of compressed gas containers arenot limitations of the invention.

FIGS. 6 and 7 depict an alternative embodiment of a compressed gas unit112 a wherein venous components of the gas unit 112 a are enclosed in ahousing 175 a. The components of the compressed gas unit 112 a aredesignated by reference numerals that correspond to those of thepreviously described embodiment and further include lower case “a”designations. In particular, a CO₂ cartridge 118 a is connected by apuncture valve 126 a to a regulator 143 a. The regulator is controlledby an adjustment knob 130 a. The regulator 143 a is connected through aconduit 154 a to both a pressure gauge 152 a and a solenoid 155 a. Moreparticularly, the pressure gauge 152 a is connected to a coupling 148 a.The solenoid 155 a is powered by a battery 165 a, which is itself heldin place within the housing by a holder 142 a. A user accessible Luerfitting 125 a is communicably connected to the solenoid 155 a andextends exteriorly of the housing 175 a.

The compressed gas unit 112 a is activated to selectively open thesolenoid 155 a by manually engaging the switch 137 a through voluntaryfingertip pressure. This transmits the pressure regulated CO₂ or othergas through the solenoid 155 a and the fitting 125 a. The compressed gasunit 112 a thereby operates in a manner analogous to that previouslydescribed to provide pressure adjusted CO₂ from the cartridge 118 athrough the Luer fitting 125 a to the flow control system or otherdestination for the medical gas. The following are preferred examples ofsuch applications.

As briefly mentioned above, the compressed gas cylinder 18, 118 issecured to the compressed air unit 12, 112 by a cartridge puncture valve22, 126 as is commonly known. In accordance with one embodiment, thecompressed gas cylinder 18 is a 25 g cylinder. Alternative capacities(e.g. 16, 36, 45 grams) may be used within the scope of this invention.Compressed air leaves the regulator valve assembly 26 at the regulatoradjusted pressure and goes to the outlet port 20. The compressed gascylinder is a single use gas supply prepared specifically for thepurpose of medical procedures. This overcomes contamination issues andprovides for the knowledge that the procedure is being performed in asanitary and safe manner Knowledge of the sources of contamination andhow to avoid them is imperative but relatively simple. During theinception of intravascular use of CO₂, Hawkins found that routine,reusable cylinders contained carbonic acid, rust, particulate matter andwater. Hawkins I F, Caridi J G. Carbon dioxide (CO2) digital subtractionangiography: 26 year experience at the University of Florida. EurRadiol. 1998; 8(3):391-402. It is essential, therefore, that disposablesources of at least medical-grade CO₂ be utilized. The present inventionprovides for the use of research grade CO₂, which is more pure andprovides for safe procedures with no need to worry about contamination.Not only does this avoid inappropriate embolization but it also avoidspain for the patient.

Referring to FIGS. 2 and 5, the compressed gas cylinder 18, 118 iscomposed of a disposable aluminum cartridge accommodating a compressedmedical gas. It should be understood that cartridge is suitable forholding a wide variety of medical gases including, but not limited to,carbon dioxide, oxygen and nitrous oxide. Cartridge is capable ofholding virtually any type of medical gas in a pressurized condition foruse in various types of medical procedures. The type of gas and the typeof medical applications involved are not limitations of this invention.

The cartridge 18, 118 includes a generally cylindrical canister body 80,180 having an elongate shape with a rounded bottom 82, 182. The canisterbody 80, 180 encloses an interior chamber 84, 184 for holding acompressed medical gas. The canister body 80, 180 includes a taperedneck portion 86, 186 that is joined to and terminates in a reduceddiameter cylindrical end portion 88, 188. The canister body 80, 180,tapered neck portion 86, 186 and reduced diameter cylindrical endportion 88, 188 thereby define a canister 90, 190 that is preferablycomposed of aluminum. The cylindrical end portion 88, 188 is preferablyencircled by a thread 92, 192 that allows the canister 90, 190 to bescrewed into a complementary threaded opening of a piece of thecompressed gas unit 12, 112. The optimum thread size is ⅜″ although itcan vary from ¼ to 1″ within the scope of this invention.

In radiological applications, the canister 90, 190 is used to holdcarbon dioxide in the chamber 84, 184 and the threaded reduced diametercylindrical end portion 88, 188 may be engaged with the portable medicalgas delivery system produced under the trademark CO₂Mmander® asdisclosed in U.S. patent application Ser. Nos. 13/068,880 and12/652,845, the disclosures of which are incorporated herein byreference. Although the cartridge is particularly convenient andeffective for use with this system, it may be used in a wide variety ofother medical applications and for holding venous other types ofcompressed medical gases.

Reduced diameter cylindrical end portion 88, 188 includes an opening 94,194 in communication with interior chamber 84, 184. The distal end ofreduced diameter cylindrical end portion 88, 188 of the canister 90, 190carries a pierceable tip 96, 196 that seals opening 94, 194 afterpressurized medical gas has been introduced into the interior ofcanister 90, 190. The tip 96, 196 may comprise a fairly thin andflexible foil that is securely sealed over opening 94, 194 in thecylindrical end portion 88, 188. The tip 96, 196 is readily punctured ina conventional manner to open canister 90, 190 so that compressed gaswithin the canister 90, 190 is made available for delivering throughopening 94, 194 to a desired medical application or use.

The canister 90, 190 is composed and constructed to provide significantadvantages. In particular, the canister 90, 190 has a relatively compactsize and configuration and is extremely lightweight especially whencompared with standard full-sized tanks conventionally used to containcompressed medical gases. In particular, the preferred weight ofcanister 90,190 is 25 grams, although it can range from 12 to 50 grams.The canister 90, 190 employs a triple-washed aluminum construction,which maintains the sterility and purity of gases contained within thecanister 90, 190. In particular, the triple-washed canister 90, 190resists the formation of mold and rust, as well as the collection ofother types of debris within the interior chamber 84, 184 of thecanister 90, 190. As a result, the integrity of the canister 90, 190 ismaintained so that the contained gas is suitable for medical use whereinnigh levels of purity and sterility are indispensable.

The compact and relatively small size of the cartridge allows thecartridge to be transported and manipulated easily and conveniently.Replacement and disposal of the cartridge are facilitated. Bulky, heavyand cumbersome tanks are avoided.

The compact cartridge is disposable and therefore does not have to berefilled or cleaned between uses. This reduces the time, logisticcomplexity and tedium required to transport and refill conventionaltanks. It also helps to maintain the sterility and purity of thecompressed medical gas contained within the cartridge. The lightweight,disposable aluminum cartridge disclosed herein therefore provides for anumber of significant advantages over the large bulky and cumbersometanks used in the prior art.

From the foregoing it may be seen that the apparatus of this inventionprovides for a disposable aluminum cartridge for accommodatingcompressed medical gases such as carbon dioxide, oxygen, nitrous oxideand the like.

As briefly mentioned above, the system relies upon the both thecompressed gas unit 12 and a multi-part valve delivery system 14 toachieved controlled delivery of CO₂. The multi-part valve deliverysystem 14, which includes a flow control system 1010 as discussed belowin greater detail, results from a realization that an improved,foolproof mechanism for safely delivering controlled amounts of amedical fluid such as CO₂ or other contrast media to a patient may beaccomplished by utilizing a multi-part valve assembly that delivers thefluid in precisely controlled amounts sequentially through a series ofsyringes such that it is impossible to directly connect the fluid sourceto the patient. At the same time, the delivery system does not have tobe disconnected and reconnected during the administration of medicalfluid. This greatly reduces the intrusion of air into the system and thefluid being administered.

For years, it has been reported that the patient should never beconnected directly to a source of compressed gas. However, themulti-part valve delivery system 14 obviates this problem since themulti-part valve delivery system 14 precludes the possibility of CO₂passing directly from the source of compressed gas, in this case, asingle does compressed cylinder. As will be appreciated based upon thepresent disclosure, the present delivery systems employs a compactcompressed gas unit 12 that uses a small 10,000-cc canister ofpharmaceutical-grade CO₂. Such a smaller system can be placed in asterile sleeve or left beneath the sterile drape. By connecting themulti-part valve delivery system 14 between the compressed gas cylinderand the patient, direct communication with the patient is prevent. Aswill be explained below, the CO₂ is introduced into a reservoir syringe(that is, the first syringe 1080 as discussed below). From the reservoirsyringe, the gas should be pushed, not aspirated, to the deliverysyringe (that is, the second syringe 1084 as discussed below) to avoidthe unlikely possibility of air contamination through the control valveassembly 1016. Equilibrium with the atmosphere can be achieved with a3-way stopcock on the delivery catheter. The system does not requireassembly and is extremely user friendly. Set-up for use takesapproximately 1 minute. The multi-part valve delivery system 14 providesfor controlled delivery of a medical fluid from a source of such fluidto a patient. As will be explained below in greater detail, themulti-part valve delivery system 14 includes an inlet conduit 1012 thatis communicably joined to a source of the medical fluid via thecompressed gas unit 12 and an outlet conduit 1014 that is communicablyjoined to the patient. First and second syringes 1080, 1084 areintermediate the inlet and outlet conduits 1012, 1014. A control valveassembly 1016 interconnects the inlet and outlet conduits 1012, 1014 aswell as the intermediate first and second syringes 1080, 1084. Thecontrol valve assembly 1016 is alternatable between first, second, andthird states. In the first state, the inlet communicates with the firstsyringe 1080 for transmitting fluid from the source to the first syringe1080. In the second state, the first syringe 1080 communicates with thesecond syringe 1084 and is isolated from the inlet and the outletconduits 1012, 1014 for transmitting fluid from the first syringe 1080to the second syringe 1084. In the third state, the second syringe 1084communicates with the outlet conduit 1014 and is isolated from the inletconduit 1012 and the first syringe 1080. This allows fluid to betransmitted from the second syringe 1084 to the patient through theoutlet conduit 1014.

In one embodiment, the control valve assembly includes a valve bodyhaving aligned inlet and outlet passageways that are communicablyconnectable to the inlet and outlet conduits respectively. The valvebody further includes a pair of first and second transverse passagewaysthat extend axially transversely to the inlet and outlet passageways andtransversely to each other. A stopcock is mounted rotatably within thevalve body and includes an angled channel having a pair of communicablyinterconnected channel segments that extend axially at an acute angle toone another. The channel segments of the stopcock are interconnected atan angle that is generally equivalent to the angle formed between eachadjacent pair of non-aligned passageways in the valve body such that thestopcock is rotatable to align the channel segments with a selectedadjacent pair of the non-aligned passageways to permit fluidcommunication between those passageways. Each of the transversepassageways is connectable to a respective syringe. The stopcock isselectively adjusted between first, second and third positions. In thefirst position, the channel segments communicably interconnect the inletpassageway and a first one of the transverse passageways. Fluidintroduced through the inlet conduit portion is thereby transmittedthrough the inlet passageway and the channel of the stopcock to thefirst transverse passageway. This passageway directs the fluid to afirst syringe attached thereto. In the second valve position, thestopcock aligns the channel segments with the first and secondtransverse passageways respectively. This isolates the fluid in thefirst syringe from both the inlet and outlet conduits. The first syringeis operated to direct the fluid through the first transverse passageway,the stopcock channel and the second transverse passageway into a secondsyringe joined to the second transverse passageway. In the third valveposition, the stopcock is rotated to align the channel segments with thesecond transverse passageway and the outlet passageway respectively.This isolates the fluid in the second syringe from the fluid source, theinlet passageway and the first transverse passageway. The second syringeis then operated to drive the fluid through the second transversepassageway, the channel of the stopcock and the outlet passageway to theoutlet conduit. The outlet conduit directs this fluid to the patient.

There is shown in FIGS. 1 and 8 the flow control system 1010 fordelivering controlled dosages of a medical contrast fluid such as carbondioxide (CO₂) for use in the radiological imaging of arteries and veinsof a patient's vascular system. Although this is a preferred applicationfor the flow control system 1010, it should be understood that the flowcontrol system 1010 may be used for the controlled delivery of variousother types of liquids and gases administered as part of assortedsurgical and medical procedures. As used herein, the term “fluid” shouldbe understood to include various types of medical liquids and gases. Bythe same token, when “gas” is used herein, it should be understood thatsuch description is likewise applicable to various types of medicalliquids.

The flow control system 1010 includes an inlet conduit 1012 and anoutlet conduit 1014 interconnected by a three-stage K-valve shapedcontrol valve assembly 1016. The inlet conduit 1012 communicablyinterconnects a source of carbon dioxide from the compressed gas unit12, 112 with the control valve assembly 1016. The outlet conduit 1014likewise communicably interconnects a discharge end of the control valveassembly 1016 with a catheter 1018 that is, in turn, operably connectedto a patient, not shown.

The inlet conduit 1012 includes a Luer fitting 1020 having a G-tube seal1022, which is selectively attached to the source of medical fluid, suchas the CO₂ source. It should be understood that flow control system 1010may be used with various sources of carbon dioxide including, but notlimited to, pressurized tanks, bags and the CO₂Mmander® manufactured byPMDA, LLC of North Fort Myers, Fla., which is described above withreference to FIGS. 1 to 3. A one-way directional valve 1024 with a Luerfitting 1026 is communicably joined to the fitting 1020. The Luer™Fitting 1026 is, in turn, communicably joined to a coiled medical tube1028 having a length of approximately 18 inches. Various alternativelengths may be employed within the scope of this invention. The distalend of the tube 1028 carries a Luer fitting 1030.

The three-stage control valve assembly 1016 includes a generallyK-shaped valve body 1032, which is preferably composed of variousmedical grade plastics, metals and/or metal alloys. Typically, the valvebody 1032 includes a molded or otherwise unitary construction. Moreparticularly, the valve body 1032 includes aligned intake and dischargebranches 1034 and 1036, respectively, which, as best shown in FIG. 8,include respective aligned internal passageways 1038, 1040. The valvebody 1032 also includes first and second transverse legs 1042, 1044.Each leg 1042, 1044 extends at an angle of substantially 60 degrees fromaligned intake and discharge branches 1034, 1036 of the valve body 1032.The first leg 1042 includes an interior passageway 1046 and the secondleg 1044 includes an interior passageway 1048, which extend axiallylongitudinally through the respective first and second legs 1042, 1044.The passageways 1046, 1048 form angles of substantially 60 degreesapiece with the respective axial passageways 1038, 1040 of the alignedintake and discharge branches 1034, 1036. The transverse first andsecond legs 1042, 1044 also extend at an angle of substantially 60degrees to one another. By the same token, the longitudinal axes of thepassageways 1046, 1048 form an angle of substantially 60 degrees.

The control valve assembly 1016 further includes a stopcock 1059 that,best shown in FIGS. 1 and 8, which is rotatably mounted within valvebody 1032. The stopcock 1059 includes an angled channel 1061 comprisingcommunicably interconnected channel segments 1063, 1065 havingrespective longitudinal axes that extend at an angle of approximately 60degrees to one another. As used herein, “approximately 60 degrees”should be understood to mean that the angle formed between therespective longitudinal axes of the channel segments 1063, 1065 issubstantially equivalent to the angle formed between the longitudinalaxes of respective pairs of the non-aligned adjacent passageways ofvalve body 1032 (e.g. respective pairs of passageways 1038, 1046; 1046,1048; and 1048, 1040). This enables the channel segments 1063, 1065 tobe communicably aligned with a selected pair of the passageways in themanner described more fully below. It should be understood that inalternative embodiments the passageways and channel segments may haveother corresponding angles. This is particularly applicable when theintake and discharge passageways and/or the inlet and outlet conduitsare not aligned.

As shown in FIGS. 1 and 8, a valve lever 1067 is mounted to the valvebody 1032 for selectively rotating the stopcock 1059 into a selected oneof three positions. For example, the stopcock 1059 is positioned withchannel segments 1063, 1065 of angled channel 1061 communicably alignedwith adjacent passageways 1038, 1046, respectively (see FIG. 9A).Alternately, and as described more fully below, the lever 1067 may bemanipulated to align the channel segments 1063, 1065 with respectivepassageways 1046, 1048 as indicated by the channel shown in phantom inposition 1061 b (see FIG. 9B). The lever 1067 may be likewise operatedto align the respective channel segments 1063, 1065 with passageways1048, 1040 as indicated by the angled channel 1061 in position 1061 c(see FIG. 9C). Such selective positioning of the stopcock 1059 providesfor controlled multiple stage delivery of fluid through the controlvalve assembly 1016 from the inlet conduit 1012 to the outlet conduit1014. This operation is described more fully below.

The intake branch 1034 of the valve body 1032 carries a complementaryfitting for communicably interconnecting to the Luer fitting 1030carried at the distal end of the tubing 1028. By the same token, thedischarge branch 1036 of the valve body 1032 carries a complementaryfitting for operably and communicably interconnecting with a Luerfitting 1050 carried at the proximal end of the outlet conduit 1014. Theremaining elements of the discharge conduit are described more fullybelow. Aligned passageways 1038 and 1040 of the valve body 1032 includerespective one-way valves 1052 and 1054, which restrict or limit theflow of fluid within the respective passageways 1038 and 1040 to thedirection indicated by arrows 1056 and 1058.

As further illustrated in FIGS. 1 and 8, the outlet conduit 1014features a coiled medical tube 1060 that is communicably interconnectedbetween the Luer fitting 1050 attached to the discharge branch 1036 ofthe valve body 1032 and a second Luer fitting 1062, which iscommunicably joined to a downstream valve 1064. The downstream valve1064 includes a one-way valve 1066 that restricts fluid flow from thetubing 1060 through the valve 1064 to the direction indicated by arrow1068. The valve 1064 features a G-tube seal 1073 that prevents air fromintruding into the system prior to connection of the valve 1064. Thevalve 1064 also includes a stopcock 1070 that is rotatably operatedwithin the valve 1064 to selectively bleed or purge fluid from the flowcontrol system 1010 through a port 1072. Exit port 1074 is selectivelyjoined to patient catheter 1018. Various alternative two and three portstopcocks may be used in the downstream valve.

A reservoir syringe 1080 is communicably connected to axial passageway1046 of the first valve leg 1042. Such interconnection is accomplishedby a conventional Luer fitting 1082, the details of which will be knownto persons skilled in the art. Similarly, a second, draw-push syringe1084 is releasably attached by a Luer fitting 1086 to the distal end ofthe second valve leg 1044. This allows the second syringe 1084 to becommunicably interconnected with the passageway 1048 through the secondtransverse leg 1044. The first and second syringes 1080 and 1084 areconstructed and operated in a manner that will be known to personsskilled in the art.

The flow control system 1010 is operated to deliver CO₂ or other medicalfluid to a patient in a controlled and extremely safe and reliablemanner. This operation is performed as follows.

The inlet conduit 1012 is first interconnected between a source ofcarbon dioxide via the compressed gas unit 12, 112 and the intake branch1034 of the valve body 1032. The outlet conduit 1014 likewise iscommunicably interconnected between the discharge branch 1036 of thevalve body 1032 and the downstream valve 1064, which is itself attachedto the patient catheter 1018. The first and second syringes 1080 and1084 are joined to the first and second valve legs 1042 and 1044 suchthat the first and second syringes communicate with the respectivepassageways 1046 and 1048. The syringes should be selected such thatthey have a size that accommodates a desired volume of gas to beadministered to the patient during the radiological imaging or othermedical/surgical procedure.

After multistage K-control valve assembly 1016 has been interconnectedbetween the inlet and outlet conduit 1012 and 1014, and followingattachment of the syringes 1080 and 1084 to the respective valve legs1042 and 1044, the stopcock 1059 is operated by the valve lever 1067 toalign the legs 1063 and 1065 of the stopcock channel 1061 with the valvepassageways 1038 and 1046 respectively (see FIG. 8). The source of CO₂is then opened or otherwise operated as required to deliver gas throughthe inlet conduit 1012 to the control valve assembly 1016. Moreparticularly, and with reference to FIGS. 8 and 9A, the gas is deliveredthrough the one-way valve 1024 and the tubing 1028 to the inletpassageway 1038. The one-way valve 1052 prevents backflow of gas intothe coil tubing 1028. The CO₂ proceeds in the direction indicated byarrow 1056 and is transmitted through the angled stopcock channel 1061into the passageway 1046 of the first valve leg 1042. From there, thegas proceeds as indicated by arrow 1090 through the fitting 1082 andinto the reservoir first syringe 1080. The CO₂ is introduced into thereservoir first syringe 1080 in this manner until it fills the syringe.

When the reservoir first syringe 1080 is filled, the operatormanipulates lever 1067, FIG. 1, and rotates the control valve into thesecond stopcock channel position represented in phantom by 1061 b inFIG. 8 (and as shown in FIG. 9B). In that position, the channel segment1063 is communicably aligned with the passageway 1046 and the channelsegment 1065 is communicably aligned with the passageway 1048. Theplunger 1081 of the reservoir first syringe 1080 is pushed and the gaspreviously deposited into the reservoir first syringe 1080 istransmitted through the passageway 1046 and the angled stopcock channel1061 b into the passageway 1048. From there, the gas is introduced intodraw-push syringe 1084 as indicated by arrow 1092. As this operationoccurs, only the transverse passageways and their attached syringes arecommunicably connected. Both syringes 1080, 1084 remain completelyisolated from both the inlet passageway 1038 and the dischargepassageway 1040. By the same token, the source of carbon dioxide andcommunicably joined intake passageway 1038 are isolated from thedischarge passageway 1040 and the outlet conduit 1014 connected to thecatheter 1018. The patient is thereby safely protected against beinginadvertently administered a dangerous dosage of carbon dioxide directlyfrom the source.

After the gas is transferred from the reservoir first syringe 1080 tothe push-draw second syringe 1084, the operator manipulates the valvelever 1067 to rotate the stopcock 1059 to the third position, which isrepresented by the stopcock channel in position 1061 c (and as shown inFIGS. 8 and 9). Therein, the channel segment 1063 is communicablyaligned with the passageway 1048 and the channel segment 1065 issimilarly aligned with the channel segment 1040. To administer the CO₂in the second syringe 1084 to the patient, the plunger 1083 of thesecond syringe 1084 is depressed in the direction of arrow 1096. Gas isthereby delivered through the passageway 1048 and the stopcock channelinto the passageway 1040. From there, the gas passes in the directionindicated by arrow 1058 through one-way valve 1054 and into tubing 1060.CO₂ is thereby transmitted in the direction indicated by arrow 1058through the one-way valve 1054 and into the tubing 1060 of the outletsection 1014. The one-way valve 1054 prevents backflow of gas into theK-valve control assembly 1016.

The lever 1067 may be configured as an arrow or otherwise marked toinclude an arrow that points in the direction of the intended fluidflow. With the lever pointing toward the reservoir first syringe 1080,as shown in FIG. 1, the angled channel 1061 is in the position shown inFIGS. 8 and 9A, fluid flow is directed toward the reservoir firstsyringe 1080. Alternatively, the lever 1067 may be rotated to pointtoward the second syringe 1084. In this position, the channel is in theposition 1061 b shown in FIGS. 8 and 9B and CO₂ is directed from thefirst syringe 1080 to the second syringe 1084. Finally, in the thirdstage of the process, the lever 1067 may be directed to point toward thedischarge end of the passageway 1040 and the attached outlet section1014. In this stage, angled channel 1061 is directed to the position1061 c, shown in FIGS. 8 and 9C, such that fluid flow is directed fromsecond syringe 1084 to the outlet section 1014.

CO₂ is delivered through the tube 1060 and into the downstream valve1064. Once again, a one-way valve 1066 prevents the backflow of gas intothe tubing. The stopcock 1070 is operated, as required, to either directthe CO₂ to the catheter 1018 and thereby to the patient, or to purge thegas through port 1072. The G-tube seal 1073 prevents air from enteringthe line.

Accordingly, the flow control system 1010 enables controlled amounts ofCO₂ to be delivered to the patient in a safe and reliable manner. Afterthe components are connected, they may remain connected during theentire medical procedure and do not then have to be disconnected andreconnected. This minimizes the possibility that air will intrude intothe system and endanger the patient. Controlled and precise dosages ofCO₂ are delivered, by the simple and foolproof operation of the controlvalve assembly 1016, from the reservoir first syringe 1080 to thepush-draw second syringe 1084 and then to the patient. At each stage ofthe process, the inlet and outlet ends of the valve remain totallyisolated from one another so that the risk of administering an explosiveand potential deadly dose of CO₂ is eliminated.

FIG. 10 again discloses the discharge branch 1036 of the control valveassembly 1016. A one-way valve 1054 is again installed in the passageway1040 to prevent backflow of gas into the control valve assembly 1016. Inthis version, the tube 1060 is communicably connected between thedischarge branch 1036 and a fitting 1100 that may be used selectively toperform various functions. In particular, the fitting 1100 includes aone-way valve 1102 that prevents backflow of gas into the tube 1060. Thefitting 1100 includes a Luer fitting 1104 that allows the fitting 1100to be releasably attached to the catheter 1018. A flush port 1106 iscommunicably joined with the fitting 1100 and features a G-valve seal1108 that permits a syringe (not shown) to be interconnected to the port1106. This syringe may be used to administer medications through thefitting 1100 to the attached catheter 1018. As a result, suchmedications may be administered to the patient without having todisconnect the individual components of the fluid delivery system. Thissaves valuable time in a surgical or medical environment and reduces therisk that air will be introduced into the system. A syringe may also beattached to port 1106 to purge or flush the catheter as needed ordesired.

FIG. 11 depicts still another embodiment of this invention wherein themedical tube 1060 is communicably interconnected between the dischargebranch 1036 of the control valve assembly 1016 and a fitting 1100 a. Thedownstream fitting again includes a one-way valve 1102 a for preventingthe backflow of gas or medication into the tube 1060. A Luer fitting1104 a releasably interconnects the fitting 1100 a to the catheter 1018.An inlet/discharge port 1108 a is formed in the fitting 1100 a forselectively introducing medication into the patient catheter through thefitting 1100 a or alternatively purging or flushing the catheter asrequired. A line 1110 is communicably connected to port 1108 a andcarries at its opposite end a Luer fitting 1112 for releasably attachingthe line to a syringe 1114. The syringe 1114 is attached to the line1100 through the fitting 1112 in order to optionally deliver medicationto the catheter 1018 through the fitting 1100 a in the directionindicated by arrow 1116. Alternatively, fluid may be purged or flushedin the direction of arrow 1121 from the catheter and/or from the systemthrough the line 1110 by drawing the plunger 1120 of the syringe 1114rearwardly in the directions indicated by arrow 1122.

In alternative versions of this invention, medical fluid may betransmitted from a source to a patient in multiple stages, as describedabove, but utilizing multiple valves joined to respective syringes. Inparticular, in a first stage operation, gas or other fluid underpressure is delivered from the source through a first directional valveto a reservoir syringe communicably connected to the first valve. Thereservoir syringe is also connected through the first valve to a secondvalve which is, in turn, communicably joined to a second syringe. Thefirst valve is operated so that the reservoir syringe remains isolatedfrom the second valve as fluid is delivered from the source to the firstsyringe through the first valve. When a selected volume of fluid isaccommodated by the first syringe, the first valve is operated toconnect the first syringe with the second valve. The second valve itselfis operated to communicably connect the first syringe to the secondsyringe while, at the same time, isolating the second syringe from thepatient. The second syringe is a push-draw syringe. The first syringe isoperated with the second valve in the foregoing position to transmit thefluid from the first syringe to the second syringe. During this stage ofthe operation, both syringes remain isolated from the source and thepatient. As a result, even if fluid under pressure is “stacked” in thereservoir syringe, this pressure is not delivered to the patient.Rather, the desired volume of the fluid is delivered instead to thepush-draw syringe. The second valve is then operated to communicablyjoin the push-draw syringe to the patient/patient catheter. Once again,the patient and catheter are totally isolated from the source of fluidunder pressure. As a result, a safe and selected volume of fluid isdelivered from the push-draw syringe to the patient.

Various valve configurations and types of directional valve may beemployed to perform the multi-stage delivery described above. In allversions of this invention, it is important that fluid first bedelivered from a fluid source to a first syringe and then deliveredsequentially to a second syringe. Ultimately, the fluid in the second,push-draw syringe is delivered sequentially to the patient. During eachstage of the process, the source of fluid remains isolated from thepatient. Typically, only one stage of the system operates at any giventime.

There is shown in FIG. 12 an alternative control valve assembly 1016 a,which again features a generally K-shaped valve body 1032 a composed ofmaterials similar to those previously described. Aligned inlet andoutlet conduit segments 1034 a, 1036 a, as well as transverse or angledconduit segments 1042 a and 1044 a are selectively interconnected tocommunicate and transmit fluid flow through respective pairs of theconduits by a rotatable stopcock valve analogous to that disclosed inthe previous embodiment. In this version, the stopcock is rotated by adual handle valve lever 1067 a, which includes elongate handles 1069 a,1071 a. These handles 1069 a, 1071 a diverge from the hub of thestopcock lever at an angle of approximately 60 degrees, which matchesthe angle between each adjacent pair of fluid transmitting conduitsegments 1034 a, 1042 a, 1044 a and 1036 a in the control valve assembly1016 a. Each of the handles 1069 a, 1071 a is elongated and carries arespective directional arrow 1073 a that is printed, embossed orotherwise formed along the handle.

The valve lever 1067 a is turned to operate the stopcock such that aselected pair of adjoining conduits is communicably interconnected topermit fluid flow therethrough. In particular, the stopcock isconstructed such that the handles 1069 a, 1071 a are aligned with andextend along respective conduits that are communicably connected by thestopcock. In other words, the valve lever 1067 is axially rotated untilthe handles 1069 a, 1071 a are aligned with adjoining conduits throughwhich fluid flow is required. The angle between the handles 1069 a, 1071a matches the angle between the adjoining conduits, e.g. 60 degrees. Thevalve lever 1067 a may therefore be rotated to align diverging handles1069 a, 1071 a respectively with either conduit segments 1034 a and 1042a, 1042 a and 1044 a, or 1044 a and 1036 a. In FIG. 12, the handles 169a, 171 a are aligned with conduit segments 1044 a and 1036 a, and arrows1073 a point in a direction that is substantially aligned with thoseconduits. This indicates that the valve lever 1067 a is rotated andadjusted such that fluid is able to flow through the valve body 1032 afrom the transverse conduit 1044 a to the outlet conduit 1036 a. Thevalve lever 1067 a is rotated to selectively align with the other pairsof conduits and thereby open the fluid flow passageway between theselected pair. The use of a dual handle valve lever 1067 a clarifies andfacilitates usage of the control valve assembly. Otherwise, the valvelever employed in the version of FIG. 12 is constructed and operatesanalogously to the valve lever disclosed in FIGS. 1, 8 and 9.

The use of multiple syringes is particularly critical and eliminates therisk of stacking that often occurs when a medical fluid is deliveredunder pressure directly from a source of fluid to a single deliverysyringe. In that case, the syringe may be filled with fluid that exceedsthe nominal volume of the syringe due to pressure stacking. If suchfluid were to be delivered directly to the patient, this could result ina potentially dangerous overdose or fluid flooding. By transmitting thefluid from a reservoir syringe into a second, push-draw syringe, thepressure is equalized and only the fluid volume and pressureaccommodated by the second syringe are delivered safely to the patient.

The present system is intended for use in methods and proceduresrequiring delivery of medical gas. The following are examples of suchapplications. CO₂ is useful in the following arterial procedures:abdominal aortography (aneurysm, stenosis) iliac arteriography(stenosis), runoff analysis of the lower extremities (stenosis,occlusion), renal arteriography (stenosis, arteriovenuous fistula [AVF],aneurysm, tumor), renal arterial transplantation (stenosis, bleeding,AVF), and visceral arteriography (anatomy, bleeding, AVF, tumor). CO₂ isuseful in the following venous procedures: venography of the upperextremities (stenosis, thrombosis), inferior vena cavography (prior tofilter insertion), wedged hepatic venography (visualization of portalvein), direct portography (anatomy, varices), and splenoportograpy(visualization of portal vein). CO₂ is likewise useful in the followinginterventional procedures: balloon angioplasty (arterial venous), stentplacement (arterial, venous), embolization (renal, hepatic, pelvic,mesenteric) transjugular intrahepatic portacaval shunt creation, andtranscatheter biopsy (hepatic, renal).

Angiography is performed by injecting microbubbles of CO₂ through acatheter placed in the hepatic artery following conventional hepaticangiography. Vascular findings on US angiography can be classified intofour patterns depending on the tumor vascularity relative to thesurrounding liver parenchyma: hypervascular, isovascular, hypovascular,and a vascular spot in a hypovascular background. Improved CTcolonography, an accurate screening tool for colorectal cancer, isperformed using a small flexible rectal catheter with automated CO₂delivery. This accomplishes improved distention with lesspost-procedural discomfort.

Carbon dioxide (CO₂) gas is used as an alternative contrast to iodinatedcontrast material. The gas produces negative contrast because of its lowatomic number and its low density compared with the surrounding tissues.As such, CO₂ doesn't mix with blood so it is not diluted. This propertypermits excellent central venous visualization from peripheralinjections using small needles. Because CO₂ doesn't mix with blood, itis not diluted and a peripheral hand injection will yield goodopacification centrally. As a result of the fact that CO₂ does not mixwith blood, when it is injected into a blood vessel, carbon dioxidebubbles displace blood, allowing vascular imaging. Because of the lowdensity of the gas, a digital subtraction angiographic technique isnecessary for optimal imaging. The gas bubble can be visible on astandard radiograph and fluoroscopic image.

Because CO₂ is present endogenously there is no concern for allergy orrenal toxicity, which has been confirmed by numerous animal and humanstudies. Hawkins I F. Carbon dioxide digital subtraction arteriography.AJR Am J Roentgenol. 1982; 139(1):19-24. Hawkins I F, Caridi J G. Carbondioxide (CO2) digital subtraction angiography: 26 year experience at theUniversity of Florida. Eur Radiol. 1998; 8(3):391-402. The viscosity ofCO₂ is 1/400 that of iodinated contrast and it is also highly soluble,roughly 20 times to 30 times greater than O₂. Therefore, it is lessocclusive than other gases. When administered intravascularly, it tendsto dissolve within a vessel in 30 seconds to 60 seconds. In intravenousadministration it is also removed from the lungs in one pass. If CO₂persists in a vessel for more than 30 seconds it is either trapped orthere is room air contamination.

As opposed to traditional liquid agents, CO₂ does not mix with blood. Infact, CO₂ is lighter than blood and floats anterior to it. To render arepresentative image it must displace the blood in the vessel. As aresult, the vessel is less dense and a negative image is obtained withdigital subtraction angiography. The quality and accuracy of the imagewill depend on the amount of blood displaced by the CO₂. Typically,smaller vessels, especially those 10 mm or smaller, demonstrate a bettercorrelation with iodinated contrast (FIG. 5). The difficulty sometimeslies in the much larger vessels where a higher volume of CO₂ isrequired. Furthermore, once the total volume of blood has beendisplaced, using a higher volume of CO₂ does not improve the vascularimage. Caridi et al. Carbon Dioxide Digital Subtraction Angiography (CO₂ DSA): A Comprehensive User Guide for All Operators. Vascular DiseaseManagement 2014; 11 (10):E221-E256.

In addition to its buoyancy, when CO₂ is administered into the vesselvia a catheter it has the potential to fragment into random bubblesdepending on how it is delivered. In an attempt to avoid this, thecatheter should be purged prior to definitive delivery and a continuous,controlled delivery of the volume of choice should be given. Dr. Chostudied the best catheter to administer a uniform, organized bolus ofgas to minimalize the bubbling effect. He found that an end-holecatheter yielded the best results.

It is also appreciated that CO₂ can easily be administered insignificant doses and has the advantage of central reflux resulting inopacification of the entire vascular structure (FIG. 12). As opposed toCO₂, contrast will only demonstrate distal to the catheter. This isespecially useful in procedures such as renal stent deployment in whichintervention is central to the catheter tip. The position of thestenosis and ostium can always be visualized using CO₂ reflux.

CO₂ insufflation for colonoscopy improves productivity of the endoscopyunit. Endoscopic thyroid resection involves creating a working spacewithin the neck using CO₂ insufflation devices, with both axillary andneck approaches as starting points for dissection. CO₂ insufflators areused during laparoscopic surgery.

Because of the lack of nephrotoxicity and allergic reactions, CO₂ isincreasingly used as a contrast agent for diagnostic angiography andvascular interventions in both the arterial and venous circulation. CO₂is particularly useful in patients with renal insufficiency or a historyof hypersensitivity to iodinated contrast medium.

CO₂ is compressible during injection and extends in the vessel as itexits the catheter. CO₂ is lighter than blood plasma; therefore, itfloats above the blood. When injected into a large vessel such as theaorta or inferior vena cava, CO₂ bubbles flow along the anterior part ofthe vessel with incomplete blood displacement along the posteriorportion. CO₂ causes no allergic reaction. Because CO₂ is a naturalbyproduct, it has no likelihood of causing a hypersensitivity reaction.Therefore, the gas is an ideal alternative. Unlimited amounts of CO₂ canbe used for vascular imaging because the gas is effectively eliminatedby means of respiration. CO₂ is partially useful in patients withcompromised cardiac and renal function who are undergoing complexvascular interventions.

Intranasal carbon dioxide is very promising as a safe and effectivetreatment to provide rapid relief for seasonal allergic rhinitis. CO₂ isused for transient respiratory stimulation; encouragement of deepbreathing and coughing to prevent or treat aterectasis; to provide aclose-to-physiological atmosphere (mixed with oxygen) for the operationof artificial organs such as the membrane dialyzer (kidney) and the pumpoxygenator; and for injection into body cavities during surgicalprocedures.

Medical asepsis is accomplished by using CO₂ with an implant deviceprior to surgical implantation. CO₂ may be effectively delivered to afoam generating tip for creating a medical foam for use in wound careand hair loss treatment.

Additionally, the present invention is used in methods requiring thedelivery of other gasses such as: Carbon Dioxide U.S.P., Medical AirU.S.P., Helium U.S.P., Nitrogen U.S.P., Nitrous Oxide U.S.P., OxygenU.S.P. and any combination thereof.

From the foregoing it may be seen that the apparatus of this inventionprovides for a system for safely delivering a controlled volume of amedical fluid in the form of a gas to a patient and, more particularlyto a system for delivery a controlled flow of carbon dioxide (CO₂) orother contrast media in order to obtain radiological images. While thisdetailed description has set forth particularly preferred embodiments ofthe apparatus of this invention, numerous modifications and variationsof the structure of this invention, all within the scope of theinvention, will readily occur to those skilled in the art. Accordingly,it is understood that this description is illustrative only of theprinciples of the invention and is not limitative thereof.

Although specific features of the invention are shown in some of thedrawings and not others, this is for convenience only, as each featuremay be combined with any and all of the other features in accordancewith this invention.

While the invention has been described in its preferred form orembodiment with some degree of particularity, it is understood that thisdescription has been given only by way of example, and that numerouschanges in the details of construction, fabrication, and use, includingthe combination and arrangement of parts, may be made without departingfrom the spirit and scope of the invention.

The invention claimed is:
 1. A method for performing a medical procedurerequiring effective and reliable delivery of controlled amounts of amedical grade gas to a patient, comprising: providing a compressed gascylinder having a weight with medical grade gas sealed therein of atleast twelve grams and not greater than fifty grams, the compressed gascylinder including an elongate, generally cylindrical body having aninterior chamber accommodating a compressed and sterile medical gradegas therein, wherein said cylindrical body is of a triple washedconstruction for holding the medical grade gas within said interiorchamber of said cylindrical body under pressure; connecting thecompressed gas cylinder to an integrated compressed gas unit includingan inlet port to which the compressed gas cylinder is selectivelyconnected and an outlet port in communication with the inlet port, theintegrated compressed gas unit also including a regulator valve assemblypositioned between the outlet port and the inlet port, wherein theregulator valve assembly includes a regulator adjustment dial; securinga flow control system to the compressed gas unit; delivering the medicalgrade gas in controlled amounts by actuating the compressed gas unit andoperating the flow control system to deliver the medical grade gas.
 2. Amethod for performing a medical procedure according to claim 1, whereinan end portion of compressed gas cylinder is encircled by a thread forattaching said cartridge to a medical apparatus requiring compressed gasof the type contained by said cartridge.
 3. A method for performing amedical procedure according to claim 2, wherein said thread is at least¼″ (6.35 mm) and not greater than 1″ (25.4 mm).
 4. A method forperforming a medical procedure according to claim 1, wherein the medicalgrade gas is CO₂.
 5. A method for performing a medical procedureaccording to claim 4, wherein the step of delivering includes deliveringCO₂ for the purpose of imaging.
 6. A method for performing a medicalprocedure according to claim 4, wherein the step of delivering includesdelivering CO₂ for the purpose of medical diagnosis and therapy.
 7. Amethod for performing a medical procedure according to claim 4, whereinthe step of delivering includes delivering CO₂ for the purpose of applyCO₂ as an alternative to iodinated contrast.
 8. A method for performinga medical procedure according to claim 4, wherein the step of deliveringincludes delivering CO, for the purpose of acting as a medical devicefor minimal access vascular procedures.
 9. A method for performing amedical procedure according to claim 4, wherein the step of deliveringincludes delivering CO₂ for the purpose of in vivo diagnostic use forcarrying solutions to stabilize micro bubbles for ultrasound,radiographic or fluoroscopic imaging.